To get this price you have to use code: LOWEPRO15 which gives you 15% discount.
Free delivery too!
Second cheapest is Amazon who sells them for £71.26.

The Lowepro Flipside 400 AW is a high-performance camera backpack designed with a large capacity, premium security, all-day comfort, plus protection from the elements. Its unique back-entry compartment provides easy access to camera gear when setting up (keeping the harness off the ground and clean of debris), plus extra security when on the move. Adjustable dividers allow custom organisation inside the roomy main compartment. Other features include: a mesh-covered, padded waistbelt, back pad and contoured straps for added comfort and wicking away moisture; a hideaway tripod holder to secure a tripod or monopod to backpack; built-in memory card pockets on inside panel; front storage panels and mesh pockets for storing additional gear; Hypalon SlipLock attachment loops for SlipLock compatible products; a built-in All Weather Cover; and silent zipper pulls. Perfect for the traveling photographer or enthusiast who needs to keep expensive gear securely tucked away, yet close at hand to capture the shot in a moment.